The recent videoconference systems allow exchange of data among a plurality of terminals through a communication network such as the Internet. The terminal sends image data and/or voice data of a user who operates the terminal, to a counterpart terminal for output through a display or a speaker of the counterpart terminal.
Further, the terminals of the recent videoconference systems may be made smaller in size such that the user may bring the terminal to any room other than the conference room to have videoconference with one or more users using the terminal. For example, the user may bring the terminal to his or her own desk or room to have videoconference using the terminal. In another example, the user may bring the terminal to his or her home to have videoconference using the terminal.
While the terminal, which may be portable, is convenient for the user, this may create the security problem as any person may be able to walk in to the place where the terminal is located to obtain information that is shared among the users having videoconference. For example, a person other than the participants of videoconference may be able to see image data being displayed through the terminal, or hear voice data being output through the terminal.